How Much Sleep Do You Need by Age? The Complete Chart

Sleep needs by age: the official chart

The table below combines the American Academy of Sleep Medicine (AASM) consensus statements for children and adults with the National Sleep Foundation's newborn range. The CDC uses the same numbers on its public guidance.

Why the ranges are so wide

A range like 7 to 9 hours reflects real differences between people. Genetics, activity, illness, pregnancy, and sleep debt all shift your personal number. The lower end is the floor for most healthy people; the upper end is normal, not excessive. Regularly needing more than the top of your range can signal poor sleep quality or a health issue worth checking.

Why teens and children need more

Growth hormone is released mostly during deep sleep, and the developing brain uses sleep to consolidate learning. Teens also experience a biological shift that pushes natural bedtime later, often past 11 p.m. This is why a 7 a.m. school start leaves so many teenagers running on 6 to 7 hours when they need 8 to 10.

Do older adults need less sleep?

No. This is one of the most common myths. The recommendation for adults 65 and older is 7 to 8 hours, barely different from younger adults. What changes is sleep quality. A large meta-analysis in the journal Sleep found that with age, people spend less time in deep sleep, wake more often, and shift toward earlier bedtimes. Older adults often feel they need less because they cannot stay asleep, not because the need has dropped.

Sleep cycles: why 90 minutes matters

Sleep is not one flat state. According to the NIH's National Institute of Neurological Disorders and Stroke, you cycle through light sleep (stages 1 and 2), deep slow-wave sleep (stage 3), and REM sleep roughly every 90 to 110 minutes. A typical night has 4 to 6 cycles.

• Early cycles are heavy on deep sleep, which restores the body and clears metabolic waste from the brain.
• Later cycles are heavy on REM, which supports memory, learning, and emotional regulation.

Two practical consequences follow. First, cutting sleep short by 2 hours does not cut 25% of everything; it cuts most of your REM. Second, waking at the end of a cycle, in light sleep, feels far easier than being pulled out of deep sleep by an alarm. This is why 6 hours (4 cycles) can feel better than 6.5, even though 6 is not enough overall. See is 6 hours of sleep enough for more.

How much should I sleep to wake up refreshed?

Work backward from your wake time in 90-minute blocks. For a 6:30 a.m. alarm, lights out at 10:45 p.m. gives five cycles (7.5 hours) plus about 15 minutes to fall asleep. Test it for a week. If you still wake groggy, shift bedtime 15 minutes earlier or later; the cycle length varies slightly between people.

Consistency versus total hours

Your circadian clock is set by regularity, not by how long you sleep. Someone who sleeps 7 hours at the same times every night usually feels more refreshed than someone who averages 7.5 hours on a schedule that swings by 2 hours between weekdays and weekends. That swing, called social jet lag, feels like flying across two time zones every Friday and back every Sunday.

The single highest-value habit is a fixed wake time, seven days a week. Morning light within an hour of waking locks the schedule in.

Is 9 p.m. a good time to sleep?

It depends on when you wake up. Nine p.m. to 5 a.m. is a healthy 8 hours for early risers. Nine p.m. to 7 a.m. is 10 hours, more than most adults need, and may cause mid-night waking. There is no magic bedtime. What matters is that it allows 7 to 9 hours before your fixed wake time and that you are sleepy when you lie down. Going to bed before you are sleepy is a common cause of lying awake.

Should you sleep 8 hours straight? Can you sleep 8 hours separately?

One continuous block is best. Deep sleep and REM are distributed across the night in a pattern that depends on continuous cycles. When you split 8 hours into two 4-hour blocks, each block restarts the pattern, so you get more light sleep and less of the restorative later-cycle REM.

That said, biphasic sleep is not harmful for everyone. Shift workers, new parents, and cultures with an afternoon siesta manage on split schedules. The rules if you must split sleep:

• Make the main block at least 5 to 6 hours so you get several full cycles.
• Keep the second block at the same time each day.
• Keep naps to 20 to 30 minutes, or a full 90 minutes, to avoid waking from deep sleep.

Sleep debt: how it builds and how to repay it

Every hour you fall short of your need is added to a running tab. In a two-week study, adults limited to 6 hours a night showed steadily worsening attention, and by the end their performance matched people who had been awake for 24 hours. They did not feel that impaired, which is what makes sleep debt dangerous.

The good news: debt can be repaid. Adding 30 to 60 minutes per night for a week or two, plus a weekend sleep no more than 1 hour past your usual wake time, gradually restores performance. Sleeping 12 hours on Saturday does not erase a week of 6-hour nights, and it shifts your clock. You cannot bank sleep in advance, though starting a hard week well-rested softens the blow.

Signs you are not getting enough for your age

• You need an alarm to wake up and hit snooze more than once.
• You fall asleep within 5 minutes of lying down (healthy is 10 to 20 minutes).
• You sleep 2 or more hours longer on days off.
• You get drowsy in warm rooms, in meetings, or while driving.
• You depend on caffeine to feel normal before noon.

If you check several of these but sleep enough hours, the problem may be quality rather than quantity. See why you're tired after 7 hours of sleep, or if you keep waking, why you wake up at 3 a.m.

Frequently asked questions